Polymers containing amino acid-based moieties are of interest for several reasons including their potential biological compatibility and biodegradability. Moreover, chiral amino acid-based polymers can have induced crystallinity, a property allowing such polymers to form higher ordered structures that exhibit enhanced solubility characteristics. These properties make such polymers ideal candidates for a variety of biomaterial applications, e.g., for drug delivery systems, biomimetic systems, biodegradable macromolecules, other biomaterials, and as chiral purification media. See, Birchall et al., Polymer 2001, 42, 375–389; Langer, R. Acc. Chem. Res. 2000, 33, 94–101; and Sanda, F. and Endo, T. Macromol. Chem. Phys. 1999, 200, 2651–2661.
Recently, Endo and coworkers have reported the synthesis of several branched and linear polymer systems containing amino acid moieties using acrylamide substrates (Sanda et al., J. Polym. Sci., Part A: Polym. Chem. 1997, 35, 2619–2629; and Murata et al., Macromolecules 1996, 29, 5535–5538); by the radical polyaddition of dithiols with diolefins (Koyama et al., Macromolecules 1998, 31, 1495–1500); as well as by the polycondensation of diols from amino alcohols and dicarboxylic acids (Koyama et al., J. Polym. Sci., Part A: Polym Chem. 1997, 35, 345–352). Circular dichroism showed that several of these polymers formed higher ordered structures. Koyama et al., Macromolecules 1998, 31, 1495–1500. In addition to the foregoing, Maynard and Grubbs have produced polymers containing amino acid moieties via the ring-opening metathesis polymerization (ROMP) of oligopeptide-substituted norbornenes, and have also copolymerized these monomers with penta(ethyleneoxide) substituted norbonenes to form water-soluble polymers. Maynard et al., Macromolecules 2000, 33, 6239–6248; Maynard, H. D. and Grubbs, R. H. Macromolecules 1999, 32, 6917–6924; and Maynard et al., J. Am. Chem. Soc. 2001, 123, 1275–1279.
Each of the foregoing methods has certain advantages and disadvantages for the production of particular types of amino acid-containing polymers. Thus, additional methods of making such polymers would advance the field. Methods that can be used with a wide range of different monomers and those that yield polymers in the form of strong films (e.g., so that they can fashioned into rigid devices) and/or with the amino acid moieties arranged in a regular pattern (e.g., for chiral separations) would be especially advantageous.